The difference is in lapack-3.6.0/CBLAS/include/cblas.h, it adds typedef before enum. For example: typedef enum {CblasRowMajor=101, CblasColMajor=102} CBLAS_LAYOUT;But in the blas/cblas.h, it only defines enum CBLAS_ORDER but not typedef. enum CBLAS_ORDER {CblasRowMajor=101, CblasColMajor=102};